[PATCH 4.9 068/120] orinoco: Use shash instead of ahash for MIC calculations

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Andrew Lutomirski <luto@xxxxxxxxxx>

commit 570b90fa230b8021f51a67fab2245fe8df6fe37d upstream.

Eric Biggers pointed out that the orinoco driver pointed scatterlists
at the stack.

Fix it by switching from ahash to shash.  The result should be
simpler, faster, and more correct.

kvalo: cherry picked from commit 1fef293b8a9850cfa124a53c1d8878d355010403 as I
accidentally applied this patch to wireless-drivers-next when I was supposed to
apply this wireless-drivers

Reported-by: Eric Biggers <ebiggers3@xxxxxxxxx>
Signed-off-by: Andy Lutomirski <luto@xxxxxxxxxx>
Signed-off-by: Kalle Valo <kvalo@xxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/net/wireless/intersil/orinoco/mic.c     |   44 ++++++++++++++----------
 drivers/net/wireless/intersil/orinoco/mic.h     |    3 +
 drivers/net/wireless/intersil/orinoco/orinoco.h |    4 +-
 3 files changed, 30 insertions(+), 21 deletions(-)

--- a/drivers/net/wireless/intersil/orinoco/mic.c
+++ b/drivers/net/wireless/intersil/orinoco/mic.c
@@ -16,7 +16,7 @@
 /********************************************************************/
 int orinoco_mic_init(struct orinoco_private *priv)
 {
-	priv->tx_tfm_mic = crypto_alloc_ahash("michael_mic", 0,
+	priv->tx_tfm_mic = crypto_alloc_shash("michael_mic", 0,
 					      CRYPTO_ALG_ASYNC);
 	if (IS_ERR(priv->tx_tfm_mic)) {
 		printk(KERN_DEBUG "orinoco_mic_init: could not allocate "
@@ -25,7 +25,7 @@ int orinoco_mic_init(struct orinoco_priv
 		return -ENOMEM;
 	}
 
-	priv->rx_tfm_mic = crypto_alloc_ahash("michael_mic", 0,
+	priv->rx_tfm_mic = crypto_alloc_shash("michael_mic", 0,
 					      CRYPTO_ALG_ASYNC);
 	if (IS_ERR(priv->rx_tfm_mic)) {
 		printk(KERN_DEBUG "orinoco_mic_init: could not allocate "
@@ -40,17 +40,16 @@ int orinoco_mic_init(struct orinoco_priv
 void orinoco_mic_free(struct orinoco_private *priv)
 {
 	if (priv->tx_tfm_mic)
-		crypto_free_ahash(priv->tx_tfm_mic);
+		crypto_free_shash(priv->tx_tfm_mic);
 	if (priv->rx_tfm_mic)
-		crypto_free_ahash(priv->rx_tfm_mic);
+		crypto_free_shash(priv->rx_tfm_mic);
 }
 
-int orinoco_mic(struct crypto_ahash *tfm_michael, u8 *key,
+int orinoco_mic(struct crypto_shash *tfm_michael, u8 *key,
 		u8 *da, u8 *sa, u8 priority,
 		u8 *data, size_t data_len, u8 *mic)
 {
-	AHASH_REQUEST_ON_STACK(req, tfm_michael);
-	struct scatterlist sg[2];
+	SHASH_DESC_ON_STACK(desc, tfm_michael);
 	u8 hdr[ETH_HLEN + 2]; /* size of header + padding */
 	int err;
 
@@ -67,18 +66,27 @@ int orinoco_mic(struct crypto_ahash *tfm
 	hdr[ETH_ALEN * 2 + 2] = 0;
 	hdr[ETH_ALEN * 2 + 3] = 0;
 
-	/* Use scatter gather to MIC header and data in one go */
-	sg_init_table(sg, 2);
-	sg_set_buf(&sg[0], hdr, sizeof(hdr));
-	sg_set_buf(&sg[1], data, data_len);
+	desc->tfm = tfm_michael;
+	desc->flags = 0;
 
-	if (crypto_ahash_setkey(tfm_michael, key, MIC_KEYLEN))
-		return -1;
+	err = crypto_shash_setkey(tfm_michael, key, MIC_KEYLEN);
+	if (err)
+		return err;
+
+	err = crypto_shash_init(desc);
+	if (err)
+		return err;
+
+	err = crypto_shash_update(desc, hdr, sizeof(hdr));
+	if (err)
+		return err;
+
+	err = crypto_shash_update(desc, data, data_len);
+	if (err)
+		return err;
+
+	err = crypto_shash_final(desc, mic);
+	shash_desc_zero(desc);
 
-	ahash_request_set_tfm(req, tfm_michael);
-	ahash_request_set_callback(req, 0, NULL, NULL);
-	ahash_request_set_crypt(req, sg, mic, data_len + sizeof(hdr));
-	err = crypto_ahash_digest(req);
-	ahash_request_zero(req);
 	return err;
 }
--- a/drivers/net/wireless/intersil/orinoco/mic.h
+++ b/drivers/net/wireless/intersil/orinoco/mic.h
@@ -6,6 +6,7 @@
 #define _ORINOCO_MIC_H_
 
 #include <linux/types.h>
+#include <crypto/hash.h>
 
 #define MICHAEL_MIC_LEN 8
 
@@ -15,7 +16,7 @@ struct crypto_ahash;
 
 int orinoco_mic_init(struct orinoco_private *priv);
 void orinoco_mic_free(struct orinoco_private *priv);
-int orinoco_mic(struct crypto_ahash *tfm_michael, u8 *key,
+int orinoco_mic(struct crypto_shash *tfm_michael, u8 *key,
 		u8 *da, u8 *sa, u8 priority,
 		u8 *data, size_t data_len, u8 *mic);
 
--- a/drivers/net/wireless/intersil/orinoco/orinoco.h
+++ b/drivers/net/wireless/intersil/orinoco/orinoco.h
@@ -152,8 +152,8 @@ struct orinoco_private {
 	u8 *wpa_ie;
 	int wpa_ie_len;
 
-	struct crypto_ahash *rx_tfm_mic;
-	struct crypto_ahash *tx_tfm_mic;
+	struct crypto_shash *rx_tfm_mic;
+	struct crypto_shash *tx_tfm_mic;
 
 	unsigned int wpa_enabled:1;
 	unsigned int tkip_cm_active:1;